For whomever is interested what i meant that i modified [Mitsubishi] PUD-SHWM100YAA to PUD-SHWM120YAA).
The 1st one has the heating capacity 10KW and the second one 12KW. These 2 models are actually IDENTICAL down to the detail (insider information). But it shouldn’t be a secret because the information is available in the installation/service manual. Now who the heck reads the manual?
Inside the unit there’s a motherboard with some DIP switches. If you buy the 10kW model the DS are aligned in a certain way that allows the pump to spin at max 110Hz, providing 10kW, in theory.
And on the unit they apply the label PUD-SHWM100YAA. A worthless sticker.
But if you buy the 12kW model you get the same unit but the DS on the motherboard are aligned in a different way allowing the pump to spin at max 118Hz (an increase of 7%) and providing 12kW. And then they put a different sticker on the unit, PUD-SHWM120YAA, and charge you 400 euros extra. That’s a god damn expensive sticker.
So long story short, somebody told me to read the manual carefully and get myself a free upgrade.
I changed the DS accordingly to the manual i my unit became PUD-SHWM120YAA.
Definitely I DO NOT RECOMMEND doing this if you don’t know what you’re doing. Frying a 10.000 euros heat pump is not funny.
7% is actually pretty good. My Samsung 8KW is basically 14KW unit crimpled in software to 8KW… So instead of modulating as low as 400W it can go only to 800W so double/triple the output in hotter days. Well done Samsung. Of course it’s not stated clearly anywhere…
Very interesting…
Do know if this applies to more units ?
I mean the following have the same min output power:
PUD-SHWM60/80
PUD-SHWM100/120
PUZ-SHWM60/80/10
hmm found them, but it suggest that the following are the same?
PUD-SWM80/100/120YAA
PUD-SHWM80/100/120/140YAA
Would love to have some free upgrades as well 
(PUHZ-SW75)
Same unit. DSs aligned in a different way.
Is it only PUD series and SW6 setting only? In the PUZ service manual it has the same table, probably typo (manual for PUZ but only layout for PUD is mentioned)
Also found it for my unit btw
I wish I could downgrade mine (PUZ-WM112VAA), as it’s twice as big as it needs to be. So I’m running with quiet mode set all the time to limit it to 50% power. That won’t help with minimum modulation though.
yours seems to be downgradeable ?
Hmm found compressor, seems different from smaller versions 
But the 60/85 seems to be upgradeable/downgradeable?
I would be extremely careful with the up/down. Mine was pretty straight forward as it had the same compressor and the same amount of refrigerant. We both looked in different manuals and we saw that even that they are part of the same family they might have different compressor and different amount of refrigerant.
As I said, mine was the same down to the last detail.
Sure looks like it (even refrigerant amount is the same), maybe @gregory75 source can confirm this model as well
@gregory75
Seems like PUHZ-SHW140 YHA is also downgradeable ? 8kW has same amount of refrigerant as 11/14kW. Maybe you can ask your source in one go
14kW → 11.2 kW seems to be exact the same. I know some user who has this way oversized unit and is having issues with it.
Switches
It sure looks like it ticks all the boxes. Turn DS 5 to OFF and DS 6 to ON and you got yourself a 112YAA. They are identical. And I cannot call “the guy” whenever someone want to do a free upgrade. He has a life and a job.
So this is how it went: he told me to read the manual. He didn’t advice me to do it so he ends up in sh*t if something goes wrong. He left the decision solely to me after i documented my self.
Then I asked myself: am I brave enough to try it? Sure as hell I am, i’m a curious guy, there’s no progress without trying.
Next question: Can I afford 5000 euros if something goes wrong? Meh. But the curiosity won.
So ask yourself these questions, the decision is YOURS and YOURS ONLY. Sure I can express my opinion (i think it’s the only thing that’s still free as of today). But don’t trust me, trust yourself!
Should you try this upgrade now during the cold season? I advice against it. If something goes wrong you gonna live with your parents again. I did it during the summer.
DO THIS ON YOUR OWN RISK!
Ah logical. If ppl have success with upgrade/downgrade, please report the models here for future reference
And don’t forget to CUT the POWER to both units, indoor and outdoor. Just don’t cut the cables
What is the benefit of downgrading? I assume the minimum modulation is down to the compressor and won’t drop, or will it?
I guess it might reduce how aggressively ramps up but wouldn’t this be the same as the quiet mode?
It will limit the maximum RPM’s to a lower maximum value. No other benefit if the minimum modulation is the same
That is correct.
I guess it’s like computer processors. Many of the silicon chips are the same, but some get sold as lower models. By overclocking the processor to a higher speed, you can gain the performance of a higher model for free.
I have a PUZ-WM85VAA could this be changed to a PUZ-WM60VAA as I believe the 6kW one is the same?
However I assume this won’t give any lower modulation benefit?